Triggers and sources of volatile-bearing plumes in the mantle transition zone

• Volatile-bearing plumes can be generated in the mantle transition zone (MTZ).
• Those plumes can be triggered by erosion of continental crust and by presence of volatiles in the MTZ.
• Volatile-bearing plumes produced abundant Meso-Cenozoic intra-continental volcanic series in Asia.

The paper discusses generation of volatile-bearing plumes in the mantle transition zone (MTZ) in terms of mineral-fluid petrology and their related formation of numerous localities of intra-plate bimodal volcanic series in Central and East Asia. The plume generation in the MTZ can be triggered by the tectonic erosion of continental crust at Pacific-type convergent margins and by the presence of water and carbon dioxide in the mantle. Most probable sources of volatiles are the hydrated/carbonated sediments and basalts and serpentinite of oceanic slabs, which can be subducted down to the deep mantle. Tectonic erosion of continental crust supplies crustal material enriched in uranium and thorium into the mantle, which can serve source of heat in the MTZ. The heating in the MTZ induces melting of subducted slabs and continental crust and mantle upwelling, to produce OIB-type mafic and felsic melts, respectively.

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